Air cleaners using vortex separators are known. The present invention is an improvement over an air cleaner of the type which is illustrated in FIGS. 1 and 2. The prior art device 10 includes a plurality of regularly arranged vortex separators 12. The vortex separators 12 extend between plates 14 and 16. Plates 14 and 16 are part of an enclosure 18 which includes an outlet 20 for scavenged air 22.
With respect to a particular vortex separator 12, a cylindrical tube 30 is snapped at one end into an opening 32 in plate 14. An ever increasing outlet nozzle 34 is centered with radial braces 36 at the other end of tube 30. The free end of nozzle 34 is snapped into an opening 37 in plate 16. Spiral baffles 38 are attached to tube 30 near the end attached to plate 14.
As vortex separator 12 receives input air 24, baffles 38 cause it to rotate and centrifugally force particulates outwardly. Cleaner air stays near the vortex and flows out nozzle 34 as depicted by arrow 28. Particulate laden air flows between tube 30 and nozzle 34 and past brackets 36 into the enclosed region between plates 14 and 16. The particulate laden air 22 is then scavenged or drawn by an exhaust system. Vortex separator 12 is not restricted at brackets 36 and allows as much air and particulates depicted by arrows 40 to flow between tube 30 and nozzle 34 as may be drawn by the exhaust system, typically an ejector, fan or other energy source connected to output tube 20.
In the prior art device 10, the scavenged flow 22 is about 10% of the input flow 24. A problem with device 10 is that it is difficult to obtain a uniform 10% scavenge from each vortex separator 12. Device 10 includes passageways 26 which are essentially vacant rows and columns in order to provide air flow to outlet 20. The problem is that the vortex separators 12 nearest outlet 20 are overscavenged and the vortex separators 12 farthest from outlet 20 may not be scavenged at all. Furthermore, passageways 26 occupy space that could otherwise contain additional vortex separators. As a result, a lesser volume of air is processed by device 10 than would be the case if passageways 26 were filled with vortex separators. In addition, the combination of reduced throughput of air and a 10% scavenge rate results in a pressure differential across downstream plate 16 in the direction of forcing scavengeable particulate laden air toward cleaned air 28 if leakage at the connection between any vortex separator 10 and plate 16 occurs. Also, the 10% scavenge requirement requires considerable exhaust system energy to achieve. Thus, the prior art device although workable, has a number of deficiencies.
The present invention improves on many of the features of device 10 and, consequently, results in an air cleaner having greater air throughput and cleaning efficiency.